There is known a configurable air cell in which a plurality of unit cells of air cells arranged in series are housed in a battery case, the battery case having a structure in which water-repellent filters are attached to ventilation holes in order to prevent liquid leakage at the time of over-discharge (for example, refer to Patent Literature 1).
There is also known a button-type air cell having a structure in which an air diffusion paper having a surface layer made of water-absorbing fiber is placed between an air electrode and a positive electrode case in order to prevent liquid leakage through air holes provided in the positive electrode case (for example, refer to Patent Literature 2).